In application Ser. No. 07/889,777 entitled “Radio Frequency Identification Device and Method of Manufacture, Including an Electrical Operating System and Method”, filed Jun. 17, 1992, now abandoned, there are disclosed and claimed new and improved radio frequency identification (RFID) tags which may be affixed to various articles (or persons) so that these articles, when shipped, may be easily tracked from the point of shipment origin, then along a given route, and then readily located upon reaching a point of destination. These RFID tags are constructed within a small area on the order of one inch (1″) square or less and of a thickness on the order of 30 mils. These tags include, among other things, an integrated circuit (IC) chip having transmitter, receiver, memory and control logic sections therein which together form an IC transceiver capable of being powered by either a small battery or by a capacitor charged from a remote RF source. The IC chip including the RF transmitter and receiver sections operates to provide for the RF signal transmission and reception to and from remote sources, and a thin film antenna is also constructed within the above small area. The above novel RFID system operates to receive, store, and transmit article-identifying data to and from the memory within the IC chip. This data is stored within the IC chip memory stage and may be subsequently called up and transmitted to an interrogating party at the above point of origin, points along a given shipment route, and then upon reaching a point of destination. This application is assigned to the present assignee and is incorporated herein by reference.
The RFID device disclosed and claimed in the above identified application represents not only a fundamental breakthrough in the field of RF identification generally, but also represents significant specific advances over the prior art described in some detail in this application. This prior art includes relatively large hybrid electronic packages which have been affixed to railroad cars to reflect RF signals in order to monitor the location and movement of such cars. This prior art also includes smaller passive RFID packages which have been developed in the field of transportation and are operative for tracking automobiles. These reflective passive RFID packages operate by modulating the impedance of an antenna, but are generally inefficient in operation, require large amounts of power to operate, and have a limited data handling capability.
The above mentioned prior art still further includes bar code identification devices and optical character recognition (OCR) devices which are well known in the art. However, these bar code identification and OCR devices require labor intensive operation and tend to be not only very expensive, but highly unreliable.